频率对两相爆震波起爆特性影响的实验研究

Experimental Research on Operating Frequency Effect on the Characteristics of Two-Phase Detonation Initiation

为了掌握爆震频率对两相多循环爆震波起爆特性的影响规律,对采用高能火花塞点火的吸气式脉冲爆震发动机不同爆震频率下的起爆过程进行了试验研究,对比分析了不同频率下的PDE沿程压力分布,讨论了起爆特征参数,如DDT转变距离、着火延迟时间、DDT转变时间和起爆时间等,与爆震频率的变化关系。试验结果显示,随着工作频率增加,爆燃燃烧向爆震燃烧的转变有所加快。工作频率对着火延迟时间和爆震形成时间影响较大,对DDT时间影响很小,随着频率增加,着火延迟时间和爆震形成时间逐渐减小,而DDT时间略有下降。

In order to grasp the influence of detonation frequency on the initiation characteristics of two-phase multi- cycle detonation, an air-breathing pulse detonation engine mockup with high energy spark plug was designed and the experiments of detonation initiation process at different operating frequencies were carried out. The pressure dis- tributions along the length of PDE mockup at different operating frequencies were contrasted and analyzed. Mean- while, the relationship between the detonation frequency on the one hand and the initiation characteristic parameters on the other hand was discussed, such as the DDT transition distance, ignition delay time, DDT transition time and detonation initiation time and so on. The experimental results indicated that deflagration to detonation transition in- creased with increasing operating frequency. The operating frequency had obvious effect on ignition delay time and the detonation initiation time but had a weak effect on DDT time. As the operating frequency increased, the ignition delay time and detonation initiation time decreased linearly, while the DDT time declined slightly.